Key to Notation

The following definitions and conventions apply throughout this section:

f	A function, or an operator's left operand (function or array).
g	A function, or an operator's right operand (function or array).
A	An operator's left argument when an array.
B	An operator's right argument when an array.
X	The left argument of a function.
Y	The right argument of a function.
R	The explicit result of a function.
[K]	Axis specification.
[I]	Index specification.
{X}	The left argument of a function is optional.
{R}←	The function may or may not return a result, or the result may be suppressed.

function may refer to a primitive function, a system function, a defined (canonical, dfn or assigned) function or a derived (from an operator) function.